721 Selection of patients for secondary cytoreductive surgery in epithelial ovarian cancer; individual assessment superior to algorithms

Introduction/Background Three phase III randomised trials have shown that patients only benefit from surgery for recurrent epithelial ovarian cancer (EOC) if complete resection is achieved. Established models to select patients with highest chance of complete resection are Arbetsgemeinschaft Gynäkologische Onkologie (AGO) and international model (iMODEL). Our aim with this study was to evaluate complete resection rate of patients undergoing secondary cytoreductive surgery (CRS) for recurrent EOC and compare algorithms for patients' selection. Methodology This is a retrospective cohort study of all patients undergoing secondary CRS, due to relapsed EOC at Uppsala University hospital from 2014 to 2023. Eligibility for secondary CRS was evaluated at multidisciplinary round based on individual patients' characteristics, radiology and laboratory findings. We calculated retrospectively AGO and iMODEL scores and estimated sensitivity and specificity for complete resection. Results We identified 149 patients with EOC that underwent secondary CRS. We excluded 20 patients with more than one secondary CRS. Mean age was 63 years. We calculated AGO and iMODEL score for the remaining 129 patients. A complete resection was achieved in 116/129 (89.9%) patients. Of the 13 patients with non-complete resection, 10 had an open-close surgery. The sensitivity for complete resection as evaluated by the AGO model was 54.3% and the specificity 46.2% (p = 0.975) and for the iMODEL - 83.6% and 16.7%, respectively (p = 1.00). Median peritoneal cancer index (PCI) was lower in patients with complete (6.3) compared to those with incomplete cytoreduction (20.0) (pConclusion In our population 89.9% of patients with EOC who underwent secondary CRS, achieved complete resection. The specificity for both AGO and iMODEL was low, indicating that these models exclude many patients who may benefit from secondary surgery. An individualized selection, preferably including preoperative estimation of PCI, may be a more accurate measure for complete secondary CRS. Disclosures None.